FreeBSD Man Pages

dtrace(1M) System Administration Commands dtrace(1M)
NAME
dtrace - DTrace dynamic tracing compiler and tracing utility
SYNOPSISdtrace [-32 | -64] [-aACeFGHhlqSvVwZ] [-bbufsz] [-ccmd]
[-Dname [=value]] [-Ipath] [-Lpath] [-ooutput]
[-sscript] [-Uname] [-xarg [=val]]
[-X a | c | s | t] [-ppid]
[-Pprovider [[predicate] action]]
[-m [provider:] module [[predicate] action]]
[-f [[provider:] module:] function [[predicate] action]]
[-n [[[provider:] module:] function:] name [[predicate] action]]
[-iprobe-id [[predicate] action]]
DESCRIPTION
DTrace is a comprehensive dynamic tracing framework for the Solaris
Operating System. DTrace provides a powerful infrastructure that per-
mits administrators, developers, and service personnel to concisely
answer arbitrary questions about the behavior of the operating system
and user programs.
The SolarisDynamicTracingGuide describes how to use DTrace to
observe, debug, and tune system behavior. Refer to this book for a
detailed description of DTrace features, including the bundled DTrace
observability tools, instrumentation providers, and the D programming
language.
The dtrace command provides a generic interface to the essential ser-
vices provided by the DTrace facility, including:
o Options that list the set of probes and providers currently
published by DTrace
o Options that enable probes directly using any of the probe
description specifiers (provider, module, function, name)
o Options that run the D compiler and compile one or more D
program files or programs written directly on the command
line
o Options that generate anonymous tracing programs
o Options that generate program stability reports
o Options that modify DTrace tracing and buffering behavior
and enable additional D compiler features
You can use dtrace to create D scripts by using it in a #! declaration
to create an interpreter file. You can also use dtrace to attempt to
compile D programs and determine their properties without actually
enabling tracing using the -e option. See OPTIONS. See the SolarisDynamicTracingGuide for detailed examples of how to use the dtrace
utility to perform these tasks.
OPTIONS
The arguments accepted by the -P, -m, -f, -n, and -i options can
include an optional D language predicate enclosed in slashes // and
optional D language action statement list enclosed in braces {}. D pro-
gram code specified on the command line must be appropriately quoted to
avoid intepretation of meta-characters by the shell.
The following options are supported:
-32 | -64
The D compiler produces programs using the native data model of the
operating system kernel. You can use the isainfo-b command to
determine the current operating system data model. If the -32
option is specified, dtrace forces the D compiler to compile a D
program using the 32-bit data model. If the -64 option is speci-
fied, dtrace forces the D compiler to compile a D program using the
64-bit data model. These options are typically not required as
dtrace selects the native data model as the default. The data model
affects the sizes of integer types and other language properties. D
programs compiled for either data model can be executed on both
32-bit and 64-bit kernels. The -32 and -64 options also determine
the ELF file format (ELF32 or ELF64) produced by the -G option.
-a
Claim anonymous tracing state and display the traced data. You can
combine the -a option with the -e option to force dtrace to exit
immediately after consuming the anonymous tracing state rather than
continuing to wait for new data. See the SolarisDynamicTracingGuide for more information about anonymous tracing.
-A
Generate driver.conf(4) directives for anonymous tracing. This
option constructs a set of dtrace(7D) configuration file directives
to enable the specified probes for anonymous tracing and then
exits. By default, dtrace attempts to store the directives to the
file /kernel/drv/dtrace.conf. You can modify this behavior if you
use the -o option to specify an alternate output file.
-bbufsz
Set principal trace buffer size (bufsz). The trace buffer size can
include any of the size suffixes k, m, g, or t. If the buffer
space cannot be allocated, dtrace attempts to reduce the buffer
size or exit depending on the setting of the bufresize property.
-ccmd
Run the specified command cmd and exit upon its completion. If more
than one -c option is present on the command line, dtrace exits
when all commands have exited, reporting the exit status for each
child process as it terminates. The process-ID of the first command
is made available to any D programs specified on the command line
or using the -s option through the $target macro variable. Refer to
the SolarisDynamicTracingGuide for more information on macro
variables.
-C
Run the C preprocessor cpp(1) over D programs before compiling
them. You can pass options to the C preprocessor using the -D, -U,
-I, and -H options. You can select the degree of C standard confor-
mance if you use the -X option. For a description of the set of
tokens defined by the D compiler when invoking the C preprocessor,
see -X.
-Dname[=value]
Define name when invoking cpp(1) (enabled using the -C option). If
you specify the equals sign (=) and additional value, the name is
assigned the corresponding value. This option passes the -D option
to each cpp invocation.
-e
Exit after compiling any requests and consuming anonymous tracing
state (-a option) but prior to enabling any probes. You can combine
this option with the -a option to print anonymous tracing data and
exit. You can also combine this option with D compiler options.
This combination verifies that the programs compile without actu-
ally executing them and enabling the corresponding instrumentation.
-f[[provider:]module:]function[[predicate]action]]
Specify function name to trace or list (-l option). The correspond-
ing argument can include any of the probe description forms
provider:module:function, module:function, or function. Unspeci-
fied probe description fields are left blank and match any probes
regardless of the values in those fields. If no qualifiers other
than function are specified in the description, all probes with the
corresponding function are matched. The -f argument can be suf-
fixed with an optional D probe clause. You can specify more than
one -f option on the command line at a time.
-F
Coalesce trace output by identifying function entry and return.
Function entry probe reports are indented and their output is pre-
fixed with ->. Function return probe reports are unindented and
their output is prefixed with <-. System call entry probe reports
are indented and their output is prefixed with =>. System call
return probe reports are unindented and their output is prefixed
with <=.
-G
Generate an ELF file containing an embedded DTrace program. The
DTrace probes specified in the program are saved inside of a relo-
catable ELF object which can be linked into another program. If the
-o option is present, the ELF file is saved using the pathname
specified as the argument for this operand. If the -o option is not
present and the DTrace program is contained with a file whose name
is filename.d, then the ELF file is saved using the name file-name.o. Otherwise the ELF file is saved using the name d.out.
-H
Print the pathnames of included files when invoking cpp(1) (enabled
using the -C option). This option passes the -H option to each cpp
invocation, causing it to display the list of pathnames, one for
each line, to stderr.
-h
Generate a header file containing macros that correspond to probes
in the specified provider definitions. This option should be used
to generate a header file that is included by other source files
for later use with the -G option. If the -o option is present, the
header file is saved using the pathname specified as the argument
for that option. If the -o option is not present and the DTrace
program is contained with a file whose name is filename.d, then the
header file is saved using the name filename.h.
-iprobe-id[[predicate] action]
Specify probe identifier (probe-id) to trace or list (-l option).
You can specify probe IDs using decimal integers as shown by dtrace-l. The -i argument can be suffixed with an optional D probe
clause. You can specify more than one -i option at a time.
-Ipath
Add the specified directory path to the search path for #include
files when invoking cpp(1) (enabled using the -C option). This
option passes the -I option to each cpp invocation. The specified
path is inserted into the search path ahead of the default direc-
tory list.
-Lpath
Add the specified directory path to the search path for DTrace
libraries. DTrace libraries are used to contain common definitions
that can be used when writing D programs. The specified path is
added after the default library search path.
-l
List probes instead of enabling them. If the -l option is speci-
fied, dtrace produces a report of the probes matching the descrip-
tions given using the -P, -m, -f, -n, -i, and -s options. If none
of these options are specified, this option lists all probes.
-m [[provider:] module: [[predicate] action]]
Specify module name to trace or list (-l option). The corresponding
argument can include any of the probe description forms
provider:module or module. Unspecified probe description fields are
left blank and match any probes regardless of the values in those
fields. If no qualifiers other than module are specified in the
description, all probes with a corresponding module are matched.
The -m argument can be suffixed with an optional D probe clause.
More than one -m option can be specified on the command line at a
time.
-n [[[provider:] module:] function:] name [[predicate] action]
Specify probe name to trace or list (-l option). The corresponding
argument can include any of the probe description forms
provider:module:function:name, module:function:name, function:name,
or name. Unspecified probe description fields are left blank and
match any probes regardless of the values in those fields. If no
qualifiers other than name are specified in the description, all
probes with a corresponding name are matched. The -n argument can
be suffixed with an optional D probe clause. More than one -n
option can be specified on the command line at a time.
-ooutput
Specify the output file for the -A , -G, and -l options, or for the
traced data itself. If the -A option is present and -o is not
present, the default output file is /kernel/drv/dtrace.conf. If the
-G option is present and the -s option's argument is of the form
filename.d and -o is not present, the default output file is file-name.o. Otherwise the default output file is d.out.
-ppid
Grab the specified process-ID pid, cache its symbol tables, and
exit upon its completion. If more than one -p option is present on
the command line, dtrace exits when all commands have exited,
reporting the exit status for each process as it terminates. The
first process-ID is made available to any D programs specified on
the command line or using the -s option through the $target macro
variable. Refer to the SolarisDynamicTracingGuide for more
information on macro variables.
-Pprovider[[predicate]action]
Specify provider name to trace or list (-l option). The remaining
probe description fields module, function, and name are left blank
and match any probes regardless of the values in those fields. The
-P argument can be suffixed with an optional D probe clause. You
can specify more than one -P option on the command line at a time.
-q
Set quiet mode. dtrace suppresses messages such as the number of
probes matched by the specified options and D programs and does not
print column headers, the CPU ID, the probe ID, or insert newlines
into the output. Only data traced and formatted by D program state-
ments such as trace() and printf() is displayed to stdout.
-s
Compile the specified D program source file. If the -e option is
present, the program is compiled but instrumentation is not
enabled. If the -l option is present, the program is compiled and
the set of probes matched by it is listed, but instrumentation is
not enabled. If none of -e, -l, -G, or -A are present, the instru-
mentation specified by the D program is enabled and tracing begins.
-S
Show D compiler intermediate code. The D compiler produces a report
of the intermediate code generated for each D program to stderr.
-Uname
Undefine the specified name when invoking cpp(1) (enabled using the
-C option). This option passes the -U option to each cpp invoca-
tion.
-v
Set verbose mode. If the -v option is specified, dtrace produces a
program stability report showing the minimum interface stability
and dependency level for the specified D programs. DTrace stability
levels are explained in further detail in the SolarisDynamicTrac-ingGuide.
-V
Report the highest D programming interface version supported by
dtrace. The version information is printed to stdout and the dtrace
command exits. Refer to the SolarisDynamicTracingGuide for more
information about DTrace versioning features.
-w
Permit destructive actions in D programs specified using the -s,
-P, -m, -f, -n, or -i options. If the -w option is not specified,
dtrace does not permit the compilation or enabling of a D program
that contains destructive actions.
-xarg [=val]
Enable or modify a DTrace runtime option or D compiler option. The
list of options is found in the SolarisDynamicTracingGuide.
Boolean options are enabled by specifying their name. Options with
values are set by separating the option name and value with an
equals sign (=).
-Xa|c|s|t
Specify the degree of conformance to the ISO C standard that should
be selected when invoking cpp(1) (enabled using the -C option).
The -X option argument affects the value and presence of the
__STDC__ macro depending upon the value of the argument letter.
The -X option supports the following arguments:
a Default. ISO C plus K&R compatibility extensions, with seman-
tic changes required by ISO C. This is the default mode if -X
is not specified. The predefined macro __STDC__ has a value of
0 when cpp is invoked in conjunction with the -Xa option.
c Conformance. Strictly conformant ISO C, without K&R C compati-
bility extensions. The predefined macro __STDC__ has a value
of 1 when cpp is invoked in conjunction with the -Xc option.
s K&R C only. The macro __STDC__ is not defined when cpp is
invoked in conjunction with the -Xs option.
t Transition. ISO C plus K&R C compatibility extensions, without
semantic changes required by ISO C. The predefined macro
__STDC__ has a value of 0 when cpp is invoked in conjunction
with the -Xt option.
As the -X option only affects how the D compiler invokes the C pre-
processor, the -Xa and -Xt options are equivalent from the perspec-
tive of D and both are provided only to ease re-use of settings
from a C build environment.
Regardless of the -X mode, the following additional C preprocessor
definitions are always specified and valid in all modes:
o __sun
o __unix
o __SVR4
o __sparc (on SPARC systems only)
o __sparcv9 (on SPARC systems only when 64-bit programs
are compiled)
o __i386 (on x86 systems only when 32-bit programs are
compiled)
o __amd64 (on x86 systems only when 64-bit programs are
compiled)
o __`uname-s`_`uname-r` (for example, __SunOS_5_10)
o __SUNW_D=1
o __SUNW_D_VERSION=0xMMmmmuuu
Where MM is the major release value in hexadecimal, mmm
is the minor release value in hexadecimal, and uuu is
the micro release value in hexadecimal. Refer to the
SolarisDynamicTracingGuide for more information about
DTrace versioning.
-Z
Permit probe descriptions that match zero probes. If the -Z option
is not specified, dtrace reports an error and exits if any probe
descriptions specified in D program files (-s option) or on the
command line (-P, -m, -f, -n, or -i options) contain descriptions
that do not match any known probes.
OPERANDS
You can specify zero or more additional arguments on the dtrace command
line to define a set of macro variables ($1, $2, and so forth). The
additional arguments can be used in D programs specified using the -s
option or on the command line. The use of macro variables is described
further in the SolarisDynamicTracingGuide.
EXIT STATUS
The following exit values are returned:
0 Successful completion.
For D program requests, an exit status of 0 indicates that pro-
grams were successfully compiled, probes were successfully
enabled, or anonymous state was successfully retrieved. dtrace
returns 0 even if the specified tracing requests encountered
errors or drops.
1 An error occurred.
For D program requests, an exit status of 1 indicates that program
compilation failed or that the specified request could not be sat-
isfied.
2 Invalid command line options or arguments were specified.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWdtrc |
+-----------------------------+-----------------------------+
|Interface Stability |See below. |
+-----------------------------+-----------------------------+
The command-line syntax is Committed. The human-readable output is
Uncommitted.
SEE ALSOcpp(1), isainfo(1), libdtrace(3LIB), driver.conf(4), attributes(5),
dtrace(7D)SolarisDynamicTracingGuide
SunOS 5.11 5 Sep 2006 dtrace(1M)